meson: Implement duplicate includes check with clang-tidy

Instead of doing this with our own script, let's use clang-tidy
instead.

tools/check-includes.py

@@ -1,32 +0,0 @@
-#!/usr/bin/env python3
-# SPDX-License-Identifier: LGPL-2.1-or-later
-
-# pylint: disable=consider-using-with
-
-import os
-import pathlib
-import re
-import sys
-
-PROJECT_ROOT = pathlib.Path(os.getenv('PROJECT_SOURCE_ROOT', '.'))
-
-def check_file(filename):
-    seen = set()
-    good = True
-    for n, line in enumerate(open(filename)):
-        m = re.match(r'^\s*#\s*include\s*[<"](\S*)[>"]', line)
-        if m:
-            include = m.group(1)
-            if include in seen:
-                try:
-                    filename = pathlib.Path(filename).resolve().relative_to(PROJECT_ROOT)
-                except ValueError:
-                    pass
-                print(f'{filename}:{n}: {line.strip()}')
-                good = False
-            seen.add(include)
-    return good
-
-if __name__ == '__main__':
-    all_good = all(check_file(name) for name in sys.argv[1:])
-    sys.exit(0 if all_good else 1)